Cam systems for circular knitting machines



Jan. 20,- 1970 H. PAEPKEZ ET AL 3,490,252

' CAM SYSTEMS FOR CIRCULAR KNITTING MACHINES Filed Nov. 15, 1967 2Sheets-Sheet 1 IN VENTORS Horsi PAEPKE Johann MARHNETZ ATTORNEY Jan. 20,1970 H. PAEPKE ET AL 3,490,252

CAM SYSTEMS FOR CIRCULAR KNITTING MACHINES Filed Nov. 15, 1967 2Sheets-Sheet z IN VEN TORS:

HorsT PAEPKE Johann MARTINETZ BY Maw ATTORNEY United States Patent O3,490,252 CAM SYSTEMS FOR CIRCULAR KNITTING MACHINES Horst Paepke,Rottenburg, and Johann Martinetz, Hechingen, Germany, assignors to Mayer& Cie, Tailfingen, Wurttemberg, Germany Filed Nov. 15, 1967, Ser. No.683,247 Int. Cl. D04b 15/32 US. Cl. 66-57 Claims ABSTRACT OF THEDISCLOSURE A cam system, for a circular knitting machine, making itpossible to conveniently replace one cam with another. The cam system ofthe circular knitting machine includes a cam means which defines a trackwhich determines the positions of the needles during operation of themachine, and this track has a region where the needles are in a knittingposition. A support means which has an interior and an exterior carriesthe cam means at the interior of the support means, and the cam meanshas at least one cam which is situated at the latter region of the camtrack where the needles are in their knitting positions. A mountingmeans coacts with this one cam to removably mount the latter on thesupport means at an operating position at the interior thereof definingpart of the cam track, while at the same time mounting this one cam forremoval at the exterior of the support means from the latter withoutrequiring removal of the support means itself from the machine, so thatin this way this one cam can easily be replaced.

BACKGROUND OF THE INVENTION The present invention relates to circularknitting machines.

In particular, the present invention relates to cam systems for circularknitting machines, such cam systems defining at least one cam track forthe needles so as to determine the positions taken thereby. For example,such a cam track may coact with needle butts or with jack butts and anumber of cams which form the cam means determine the positions of theneedles.

With cam systems of this general type it is already known to renderindividual cams adjustable from the exterior. For this purpose theadjustable cams are supported in the cam system either for shifting orturning movement and are capable of being adjusted by way of a leversystem which is accessible at the exterior so as to be actuated from theoutside. It is also already known to arrange individual cams so thatthey can be disconnected from the cam system, for exchanging such camsor for selectively replacing them with other cams of differentconfigurations. For this purpose, however, it is necessary to remove theentire cam system from the machine, in order to render the control sideof the cam system body with the cam freely accessible.

SUMMARY OF THE INVENTION It is accordingly a primary object of thepresent invention to provide a cam system which makes it possible toexchange at least one predetermined cam from the exterior, so that inthis way at the location of this one exchangeable cam differently shapedcam components for guiding the needles or jacks can be respectivelyintroduced into the machine to achieve different types of knitting,without requiring the body of the cam system to be removed from themachine.

Thus, it is a more specific object of the invention to provide aconstruction which will very conveniently enable at least one cam to beremoved, by way of manipulations only at the exterior of the machine,and replaced 3,490,252 Patented Jan. 20, 1970 by another cam withmanipulations onl at the exterior of the machine, ina very convenientmanner, which does not require removal of any other components, such asthe entire body which carries a plurality of the cams.

In addition, it is an object of the present invention to provide aconstruction which will accurately determine the operating osition ofthe removable cam.

Furthermore, it is an object of the present invention to provide asimple effective structure which will reliably hold the replaceable camremovably in its operating position in the machine. 7

In accordance with the invention, the above objects are achieved byproviding at the interior a support means, which carries a cam means,which determines the track for controlling the needle positions, atleast one cam located at that region of the track where the needles arein their knitting positions and a mounting means which coacts with thisone cam to mount the latter, not only in an operating position at theinterior of the support, but also for removal from the support means atthe exterior of the latter, without requiring removal of the supportmeans itself from the machine, so that in this way it becomes possibleto remove and replace this one cam sim ply by movement of the mountingmeans and without any removal of the support means itself.

This mounting means preferably takes the form of an elongatedcylindrical carrier body which has an inner end, where the one removablecam is located, and this cylindrical carrier body is situated in a borewhich is formed in and extends through the support means at a body ofthe latter which carries the cams, this bore extending from the exteriorto the interior of this body of the support means. This one removablecam can be a tucking and clearing cam, which can be situated either in atucking or in a clearing position by turning of a shaft which isconnected to the cam and which is supported for rotary movement in abore of the cam carrying body itself, so that in this way the cam isadjustable to determine, at at least one side, the part of the trackwhere the needles are displaced either to their tucking or to theirclearing positions. However, it is also possible to situate at the innerend of the cam-carrying body, which is removable from the support meansand forms the mounting means, a stitching or knitting cam which retractsa needle from its clearing position to its idle position. Aneedle-retracting cam of this type can, for example, be situated in adial cam system 'in the case where knitting is to take place only withcylinder needles and not with dial needles. In this latter event thedial needles serve the purpose of holding down the loops which have beenknitted by the cylinder needles, when the dial needles have beenadvanced outwardly to their tucking positions, with the retracting camretracting the dial needles to their idle positions before the locationwhere the yarn is fed.

However, the cam-carrying body, which can be replaced from the exterior,can also be situated at other suitable locations of the cam track andcan then be provided with components to carry out diflerent functions.Thus, when the replaceable cam and its carrier body are located in theregion of a knitting position, it is possible for the carrier body to beprovided, for example, selectively with a tucking cam component or witha clearing cam component.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated by way ofexample in the accompanying drawings which form part of this applicationand in which:

FIG. 1 is a schematic plan view of' part of a dial knitting system of acircular knitting machine, FIG. 1 illustrating the cams of a pair ofsections of the dial cam system as seen from the interior;

FIG. 2 is a section of the structure of FIG. 1 taken along line IIII ofFIG. 1 in the direction of the arrows;

and

FIG. 3 is a plan view of part of the structure of FIG. 2 as seen in thedirection of arrow HI of FIG. 2.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to FIG. 1, there areillustrated therein a pair of sections 1 and 2 of a dial cam system of amachine having short and long needles. In order to clearly indicate theconfiguration of the tracks for the short and long needles, the trackfor the butts 3 of the short needles and for the butts 4 of the longneedles are schematically indicated in FIG. 1. The direction of movementof the needle butts 3- and 4 at the beginning and ends of the cam tracksfor the dial sections 1 and 2 is indicated by the arrows at the left andright of FIG. 1, so that the needle butts are to be considered as movingfrom left to right, although it is of course also possible, as is wellknown, to rotate the cam system with respect to the needles which inthis case will only be displaced radially.

A cam means determines in a known way the configuration of the camtracks which determine the needle positions, and this cam means is ofcourse composed of a plurality of cams which determine the configurationof the cam track. The cam tracks for the short and long needles aresubstantially the same. Therefore, the corresponding cam components forboth types of needles are referred to below with the same referencecharacters, whereas the reference characters for the components of camsystem 2 are indicated with the same reference characters primed asthose which are used for corresponding components of the cam system 1.

The cam means which is formed by the plurality of cams is carried by asupport means which includes the cam-carrying bodies 10 and 10 of thesections 1 and 2, and the cam means includes, among other cams, a pairof cams 5a and 5b which are connected together and which are radiallyshiftable between a position for displacing the needles outwardly totheir tucking position or a position for maintaining the needles intheir idle running position where they do not participate in theknitting. Thus, in FIG. 1 the interconnected cams 5a, 5b are shown forthe needle butts 3 in the position for advancing the needles to theirtucking positions and in the cam section 1 in a position for advancingthe longer needles to their tucking position, while at the section 2 theinner interconnected cams 5a and 5b are shown at their position formaintaining the longer needles in their idle running position.

The cam systems also include two-part known knitting cams 6a and 6b or6a or 6b which are radially adjustable and which serve to retract theneedles from their clearing positions so as to carry out a stitching orknitting operation, according to which one loop is pulled throughanother loop.

At the knitting region of the cam tracks, however, the needle butts 3and 4 are guided by cam components :apable of being introduced into thecam system bodies and 10' from the exterior of the support means formedthereby in a direction which is perpendicular to the plane of FIG. 1which shows the support means 10 and 10' as they appear from theinterior. As is apparent from the sectional illustration in FIG. 2, theremovable cam of the cam means is supported by a mounting means whichincludes an elongated cylindrical carrier body 7 situated in a bore 8m 9which extends through the cam system body 10. The replaceable camcomponent is fixed to the :ylindrical carrier body 7 at its inner end.In the cam system 1 the carrier bodies 7 have integrally formedtherewith retracting cam components 11 having the configuration ofsegments of a circle and forming a onepiece body with the cylindricalbodies 7, these cams 11 projecting inwardly beyond the inner ends of thebody 7.

At their outer ends the cylindrical bodies 7, which are of circularcross section, are also integrally formed in one piece with a lateralextension 12 which projects at at least one side laterally beyond thebody 7. At its projecting portion the extension 12 is formed with a borethrough which can extend a threaded screw having a knurled head so thatit can conveniently be turned by the operator for the purpose of fixingthe extension 12 to the body 10, or a positioning pin 13 can passslidably through the bore of the extension 12 into an aligned bore 14formed in the body 10 for the purpose of reliably situating the body 7at its proper angular position. The extent to which the pin 13 projectsbeyond extension 12 into the opening 14 is precisely so that it has alength which is at least equal to the axial extent to which the cam 11projects inwardly beyond the inner end of the body 7, so that when thepin 13 is not situated in the bore 14 the cam 11 is not situated at anoperating position where it forms part of the cam track of the camsystem. Furthermore, the lateral extension 12 is provided with athreaded bore to receive a bolt which facilitates removal of the body 7out of the body 10 during exchange of the cam. For this purpose a boltneed only be threaded into the tapped bore 15 so that through such abolt it is possible to pull outwardly on the body 7 to remove the latterand the cam 11 therewith.

As is apparent from the plan view of FIG. 3, the latter extension 12 hasan irregular configuration, which is in part determined by the aavilablespace at the exterior of the support means 10. The edges of the lateralextension 12 can, however, simultaneously be formed also as stops whichreliably assure a proper angular positioning of the body 7 when it isintroduced into the support means.

This body 7, which forms the mounting means for the exchangeable camcomponent is held in position by a releasable holding or fixing means inthe form of a detent device shown in FIG. 2 as including a spring-loadedball member 16 which extends into an annular groove 17 formed in thebody 7, so that in this way the body 7 together with the cam 11 aresecured in the support means 10 against undesired shifting movement.Thus, with such a construction a screw-type of fixing of the extension12 is unnecessary.

At the cam system or section 2 there are, in the same way as in FIG. 1,carrier bodies 7' which form mounting means for the exchangeable cams ofthe section 2, these latter cams being in this case earns 18 formingtucking and clearing cams. Each cam 18 is capable of selective placementeither in a tucking position or in a clearing position by way of anelongated control shaft extending longitudinally through a centralcoaxial bore of the body 7' and connected at the outer end of the latterto a lever accessible to the operator for turning the cam 18 either to atucking position or to a clearing position. Thus, the cam 18 is shown atthe track provided for the needle butts 3 in a clearing position whereit will displace the short needles from their tucking position outwardlyto a clearing position where the beards of the needles will clear theloops thereon, while the inner body 7' of FIG. 1 is shown with itsadjustable cam 18 situated at a tucking position for the needle butts 4of the longer needles. However, as will be apparent from the description below, in the illustrated example while the outer edge of thecam 18 would determine the tucking position, the inner edge of the cam18 is shown in FIG. 1

coacting with the needle butts 4 to maintain them in their idleposition, so that these cams 18 serve a dual function.

FIG. 1 shows outwardly beyond the outer edge of the dial cam systems 1and 2 the knitting path 20 taken by the short needles whose butts 3 areinitially advanced by way of the cam component 5a outwardly to thetucking position 20a at which these short needles will contribute to theoperations of the unillustrated cylinder needles, during knittingcarried out by the latter, by holding down the already knitted loops.Then the needle butts 3 engage the retracting cam 11 which serves toretract the needles along the path 20b into their idle running position20c, and, of course, had the needles been displaced outwardly to theirclearing positions, then the retracting cam 11 would have displaced theneedles inwardly during retraction thereof so as to stitch or knit bypulling one loop through another. However, since the displacement isonly in from the tucking position 20a, the needles are simply retractedwithout knitting back to their idle running position 200. The sinkercams 6a and 6b bring about the sinking movement 20d after which the dialneedles are displaced outwardly by the cams 5a of the second knittingsystem 2 so that the short needles initially reach the tucking position20c. Then these needles are displaced by the outer cam 18 to theclearing position 20f where the beards of the needles will clear theloops thereon so that subsequently the sinker cam 6a will in a known wayretract the needles to the sunk position 20g with simultaneous knittingtaking place during this retraction of the needles which previously havebeen displaced to their clearing positions.

The knitting path for the long needles is not illustrated. The butts 4of the long needles are, in contrast to the short needles, maintained inth system 2, by a corresponding positioning of the retracting cams 5aand 5b, by way of the outer retracting cam 51), in the idle runningposition indicated by the dotted knitting path section 2011. This idlerunning position is limited outwardly by the way of the inner cam 18which has been turned to its tucking position so that instead of holdingthe needles in a tucking position by its outer guiding edge the innercam 18 has its inner guiding edge coacting with the stationary cam 19,With which it is aligned, to hold the needles at their idle runningposition 20h.

The invention can of course be carried out with many different types ofconstructions. For example, the cylindrical carrier body for theremovable cam component can be secured reliably in its desired angularor circumferential position in the cam system body by way of a tongueand groove structure. The securing of the exchangeable cam component canalso take place by way of the other cam components. Thus, as shown inFIGS. 1 and 2, a cam can have a portion which extends over the openinner end of the through-bores 8 and 9. In FIG. 1 there is shown at theouter region of the system 1 at the body of the support means a camcomponents 21 provided with a notched cutout 22 which receives an edgeof the retracting cam 11 which is of the configuration of a sector of acircle, and this part of the cam 21 which is provided with the notch 22extends over the inner end of the bore 9 which receives the outer body 7of FIG. 1. In the same way, other cams can be provided with portionsextending into overlapping relation with the inner open ends of thethrough-bores 8 and 9 and formed with suitable notches to coact withreplaceable cams to determine their angular positions. A notch such asthe notch 22 prevents turning of the cam 11 in both directions.

In general it is suflicient, when knitting only with the cylinderneedles, to use either only the long needles or only the short dialneedles for participating in the knitting with the cylinder needles byway of holding down the already knitted courses or loops at the regionsof the knitting positions, so that only one of the cam paths need beprovided with replaceable cam components. Of course, the use of theinterchangeable cam component in accordance with the invention is notlimited to dial cam systems. It is possible in the same way to provide acylindrical cam system with a replaceable cam which can be replaced fromthe exterior.

What is claimed is:

1. In a cam system for circular knitting machines, cam means fordefining a track which determines needle move ment and which has aregion where needles have a knitting position, support means, having aninterior and an exterior, carrying said cam means at said interior ofsaid support means, said cam means including at least one cam situatedat said region of said track, and mounting means coacting with said onecam for removably mounting said one cam on said support means in anoperative position at said region of said track and for removal fromsaid support means at the exterior thereof without removing said supportmeans from the circular knitting machine, so that said one cam can bereplaced from the exterior of said support means.

2. The combination of claim 1 and wherein said mounting means includes acylindrical carrying body having an inner end where said one cam islocated and said support means including a body formed with an openingin which said cylindrical carrier body of said mounting means islocated, and means for releasably fixing said carrier body to saidsupport means.

3. The combination of claim 2 and wherein said one cam situated at saidinner end of said carrier body is a tucking and clearing cam, saidcylindrical body being formed with an axially extending bore in which acontrol shaft which is fixed to said one cam is located for turningmovement, so that through the latter shaft said one cam can be situatedeither in a tucking position or in clearing position, and said one camdetermining on at least one side thereof a part of the track of said cammeans.

4. The combination of claim 2 and wherein said one cam situated at saidinner end of said carrier body is a knitting cam for retracting needlesfrom their clearing positions to their idle positions.

5. The combination of claim 4 and wherein said one cam is integral withand forms a one-piece structure with said carrier body.

6. The combination of claim 3 and wherein said one cam also limits, atat least one side, a part of said track which determines the path ofidling movement of the needles.

7. The combination of claim 2 and wherein said releasable fixing meansincludes a spring-pressed detent ball carried by said support means anda recess formed in said cylindrical carrier body receiving said ball.

8. The combination of claim 2 and wherein said cylindrical carrier bodyhas an outer end carrying a fixing extension, which extends laterallyfrom said outer end of said body at the exterior of said support meansfor releasably fixing the carrier body to said support means at theexterior of the latter.

9. The combination of claim 8 and wherein said lateral extension at saidexterior of said cylindrical body is formed with an opening passingtherethrough and wherein said support means is formed with an openingaligned with said opening of said extension, and a positioning pinextending through said opening of said extension and into said openingof said support means for positioning said cylindrical body and said onecam therewith at a predetermined angular position with respect to saidsupport means.

10. The combination of claim 2 and wherein said support means has at itsinterior a projection extending across a part of said bore at an innerend thereof to be engaged by part of said one cam to determine theposition thereof at the interior of said support means.

References Cited UNITED STATES PATENTS 2,756,574 7/ 1956 Shortland 66252,895,317 7/1959 Millet et al 6624 3,158,012 11/1964 Kahan 6631 RONALDFELDBAUM, Primary Examiner

